Ta có:\(\frac{x-100}{24}+\frac{x-98}{26}+\frac{x-96}{28}=3\)

\(\Rightarrow\)\(\frac{91x-100.91}{91.24}+\frac{84x-84.98}{26.84}+\frac{78x-96.78}{78.28}\)

=\(\frac{91x-9100+84x-8232+78x-7488}{2184}\)

=\(\frac{91x+84x+78x-9100-8232-7488}{2184}\)

=\(\frac{x\left(91+84+78\right)-\left(9100+8232+7488\right)}{2184}\)

=\(\frac{x253-24820}{2184}=3\)

\(\Rightarrow\)x253- 24820 =6552

\(\Rightarrow\)x253= 31372

\(\Rightarrow\)x = 124

\(\frac{x-100}{24}+\frac{x-98}{+26}+\frac{x-96}{28}=3\)

\(=\frac{\left(x-100\right)}{24}+\frac{\left(x-98\right)}{26}+\frac{\left(x-96\right)}{28}-1=0\)

\(\Leftrightarrow\frac{\left(x-100\right)}{24-1}+\frac{\left(x-98\right)}{26-1}+\frac{\left(x-96\right)}{28-1}=0\)

\(\Leftrightarrow\left(x-124\right)\left(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\right)=0\)

Vì: \(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\ne0\)

\(\Rightarrow x-124=0\)

\(\Rightarrow x=124-0\)

\(\Rightarrow x=124\)

Ta có :\(\frac{x-100}{24}+\frac{x-98}{26}+\frac{x-96}{28}=3\)

           \(\Rightarrow\frac{91x-100.91}{91.24}+\frac{84x-84.98}{26.84}+\frac{78x-96.78}{78.28}\)

           \(=\frac{91x-100.91+84x-8232+78x-7488}{2184}\)

            \(=\frac{91x+84x+78x-9100-8232-7488}{2184}\)

             \(=\frac{x\left(91+84+78\right)-\left(9100+8232+7488\right)}{2184}\)

               \(=\frac{x253-24820}{2184}=3\)

                 \(\Rightarrow x253-24820=6552\)

                 \(\Rightarrow x253=31372\)

                  \(\Rightarrow x=124\)

a )

\(\Rightarrow\frac{x-100}{24}-1+\frac{x-98}{26}-1+\frac{x-96}{26}-1=0\)

\(\frac{x-124}{24}+\frac{x-124}{26}+\frac{x-124}{28}=0\)

\(\left(x-124\right)\left(\frac{1}{26}+\frac{1}{24}+\frac{1}{28}\right)=0\)

\(\Rightarrow x-124=0\Rightarrow x=124\)

b) 

\(\frac{x-28-124}{2011}-1+\frac{x-124-2011}{28}-1+\frac{x-2011-28}{124}-1=0\)

\(\Rightarrow\frac{x-2163}{2011}+\frac{x-2163}{28}+\frac{x-2163}{124}=0\)

\(\left(x-2163\right)\left(\frac{1}{2011}+\frac{1}{28}+\frac{1}{124}\right)=0\)

=) x - 2163 =0

x= 2163

\(\frac{x-100}{24}+\frac{x-98}{26}+\frac{x-96}{28}=3\)

\(\Leftrightarrow\frac{x-100}{24}-1+\frac{x-98}{26}-1+\frac{x-96}{28}-1=0\)

\(\Leftrightarrow\frac{x-124}{24}+\frac{x-124}{26}+\frac{x-124}{28}=0\)

\(\Leftrightarrow\left(x-124\right)\left(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\right)=0\)

Mà 1/24+1/26+1/28 khác 0

\(\Leftrightarrow x-124=0\Leftrightarrow x=124\)

\(\frac{x-100}{24}+\frac{x-98}{26}+\frac{x-96}{28}=3\)

\(\Leftrightarrow\frac{x-100}{24}-1+\frac{x-98}{26}-1+\frac{x-96}{28}-1=0\)

\(\Leftrightarrow\frac{x-124}{24}+\frac{x-124}{26}+\frac{x-124}{28}=0\)

\(\Leftrightarrow\left(x-124\right)\left(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\right)=0\)

Mà \(\frac{1}{24};\frac{1}{26};\frac{1}{28}\)khác \(0\)

\(\Leftrightarrow x-124=0\Leftrightarrow x=124\)

\(\Rightarrow\frac{x-100}{24}-1+\frac{x-98}{26}-1+\frac{x-96}{28}-1=3-1-1-1=0\)

\(\Rightarrow\frac{x-124}{24}+\frac{x-124}{26}+\frac{x-124}{28}=0\)

\(\Rightarrow\left(x-124\right)\left(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\right)=0\)

\(\Rightarrow x-124=0\) ( vì 1/24 + 1/26 + 1/28 khác 0)

=> x = 124 

\(\frac{x}{24}-\frac{25}{6}+\frac{x}{26}-\frac{49}{13}+\frac{x}{28}-\frac{24}{7}=3\)

\(x\left(\frac{1}{24}+\frac{1}{26}+\frac{1}{28}\right)-\left(\frac{25}{6}+\frac{49}{13}+\frac{24}{7}\right)=3\)

\(x\cdot\frac{253}{2184}=\frac{7843}{546}\)

\(x=124\)

A)=>x + 1/2011+ x + 1/2012 - x + 1/2013 - x + 1/2014 =0

<=>(x + 1) . ( 1/2011+ 1/2012-1/2013 - 1/2014) = 0

=>x + 1 = 0 (vì 1/2011+ 1/2012 - 1/2013 - 1/2014 khác 0)

=>x     =  -1

vậy x   =  -1

B)x-100/24+x-98/26+x-96/28=3

<=>x - 100/24 - 1 + x - 98/26 - 1 + x - 96/28 =0

<=>x - 124/24 + x - 124/26 + x - 124/28 = 0

<=>(x-124).( 1/24 + 1/26 + 1/28 ) = 0

mà 1/24 + 1/26 +1/28 khác 0

=>x - 124 = 0

<=>x       = 124